To make clean straight folds in cardboard, first make a crease along the line with a blunt edge such as a spoon handle, then fold against a firm straight edge.

为了使清洁直纸板折叠，先如勺子处理沿钝边行折痕，然后对折直边坚定。

youdao

The edge is as blunt as an old butter knife.

刃钝得跟一把老黄油刀一样。

《柯林斯英汉双解大词典》

No doubt it is the fate of all cutting-edge technology to eventually turn blunt, dull and outmoded, but that is a concern for another day, another era.

毫无疑问，所有尖端科技最终都无法逃脱愚钝、沉闷和过时的命运，但那是在另一个时代另一个日子里才需要面对烦恼。

youdao

By in effect conceding the election to Labour, and admitting that independence cannot be achieved any time soon, he hopes to blunt the edge of a Tory anti-nationalist campaign similar to that mounted in 1992.

ECONOMIST: Scottish politics: Roast Tory | The

If the Ravens set the edge and blunt Davis, Kaepernick is going to have to win with Crabtree and Moss, or Gore is going to need to have a BIG rushing day.

FORBES: What Are The 49ers' Weaknesses Heading Into The Superbowl?